Programmable integrated circuit GC-IP2000

analoginterpolationwith sinusoidal output

The interpolation circuit GC-IP2000 serves to increase the resolution for incremental position and angular measuring systems with sinusoidal output signals offset by 90°. The IC divides the signal period up to 2048 times. The GC-IP2000 comprises three instrument amplifiers with adjustable gain factors. Incremental encoders with a voltage interface and measuring bridges can be connected directly. Sensors with current interface and photodiode-arrays are adapted by a simple external circuit. The IC may operate with both single-ended and differential input signals. The noise of the sensor signals is prevented by a switching analog filter. Additionally, a digital hysteresis can suppress the edge noise of the output signals at low input frequencies and at standstill. Thus, in case of a short-time disturbance of the input signals, a subsequent interpolation counter will operate without errors. The input signals are subjected to an AMAC-specific internal gain and offset control. The amplitude is controlled in the range between 60 % and 120 % of the nominal amplitude. The control range for the offset of the two input signals is ±10 % of the nominal amplitude. The phase displacement of the input signals can be corrected statically between -10° and +10° using a digital potentiometer. The quality of the signals issued by the sensors is monitored in the IC. For that purpose it is possible to activate separately 9 sources producing an error signal.